glibc/bits/inf.h

33 lines
1.3 KiB
C

/* Default `INFINITY' constant.
Copyright (C) 2004 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#ifndef _MATH_H
# error "Never use <bits/inf.h> directly; include <math.h> instead."
#endif
/* If we don't have real infinity, then we're supposed to produce a float
value that overflows at translation time, which is required to produce
a diagnostic. GCC's __builtin_inff produces a quite nice diagnostic
that tells the user that the target doesn't support infinities. */
#if __GNUC_PREREQ(3,3)
# define INFINITY (__builtin_inff())
#else
# define INFINITY (1e9999f)
#endif